Yeah, but like I said I think he was in 3rd gear which totally skews the results, right?

It could be off make 5-10 ponies maybe, but not 20 or 30. An buddy and I tested his car on a mustang dyno (FIS in Mckinney) in 3rd & 4rd gear. The pulls were with in 5-7whp of each other. Same day. We even changed vehicle weight to see how much difference it made, wasn't that much either.

You don't have any boost leaks, correct? How do these cars behave with slight leaks? I know my S4 would have a noticable power difference when I had even a small leak.

Now, I've seen two of the same year, make model car with the same mods make 40-60whp difference on the dyno, but yet when we did 4th gear 40-120mph pulls, they were identical. Neither car was faster than the other....but every time car B got on the dyno, it was 40-60whp lower. It just didn't like the dyno. Maybe your car is like his?